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Should President Trump end 'chain migration?'

Proposals to ban human cloning will come before the Senate shortly, and the passionate debate the issue ignited last year is certain to flare anew.Senators will consider a House-passed measure that calls for a 10-year jail sentence and a $1 million fine for anyone who clones a human embryo. But since a majority of senators last year went on record supporting expanded stem-cell research, the tough House measure is unlikely to gain approval.Nonetheless, scientists say that if the Senate goes along with the House and bans all cloning, the measure would halt research in the United States that could lead to cures for some of mankind's most terrible diseases. They also predict that some of the country's top medical researchers would then move to countries where such experimentation is accepted and ongoing.The first of the nation's research stars defected in July. Citing the controversy over embryonic stem-cell science, Roger Pedersen of the University of California at San Francisco accepted a faculty position at the University of Cambridge, a center for developmental biology in the United Kingdom.As many legislators see it, though, a ban on the research is the only moral option. Sen. Sam Brownback, Kansas Republican, put it this way:"We must ban all human cloning This is an important issue because of the vast historical consequence, and also because it focuses attention on the meaning of life and whether or not we will, as a society, allow life to be created and destroyed at our whim."For Mr. Brownback and for others, the events of the past year have expanded and added a sense of urgency to the 4-year-old debate over cloning, which last year became entangled with the question of embryonic stem-cell research. When President Bush took office last year, he faced the need to decide whether to reinstitute limitations on the use of federal funds for embryonic stem-cell research. The rule had restricted experimentation by scientists working in universities and other institutions from receiving government funds for the research. The ban did not affect commercial biotechnology companies, which continued with their experiments.Among the series of basic considerations that faced the president last year and that now confront the Senate are the following: Stem cells taken from an embryo in its formative stages have the remarkable capacity to develop into any sort of bodily tissue and to form entire organs or components of organs such as the heart, brain, spine or liver.Researchers believe it is possible to coax embryonic stem cells into becoming the kinds of body parts they want. Their optimism is based on experiments with the embryos of animals, especially of mice.Stem cells that have been directed to grow into a particular organ or segment of an organ say, neurons of the brain could conceivably be injected into ailing patients to replace the damaged or injured cells that cause illnesses like Alzheimer's and Parkinson's diseases and to cure paralyzed stroke victims. Again, animal experiments indicate the possibility exists.Stem cells taken from embryos can divide endlessly and for that reason are said to be "immortal." The multiplying cells can be stored to form a repository of colonies, or "stem-cell lines." Consequently, laboratories do not need an endless supply of embryos, but just enough to start the cell lines they need.Embryos die when their stem cells are removed. Politicians, religious leaders, pro-life advocates and some ethicists thus argue that human stem-cell research is akin to murder.Scientists for the most part believe that embryos are less than human beings or persons. They consider them living organisms with the potential to become human. As such, they say, it's morally appropriate to sacrifice early-stage embryos in the service of good causes, such as curing Alzeheimer's or heart disease.Researchers typically contend that the most responsible approach is to extract cells only from embryos destined for destruction, meaning those obtained from fertility clinics that have produced a surfeit of embryos during reproduction therapy.Stem cells might well be obtained from embryos created through cloning. Massachusetts-based Advanced Cell Technology announced recently that it had cloned a human embryo and hoped to create more for use as a source of stem cells. However, some of the nation's most respected geneticists and researchers dispute the supposed breakthrough. They say the organisms that Advanced Cell created, and which quickly died, were merely agglomerations of cells, not embryos.For instance, biochemist Larry Goldstein of the University of California at San Diego echoed the thoughts of many when he commented: "Advanced Cell Technology induced human eggs to undergo a couple of divisions, but what they made was not human. Just because I walk from my lab and say, 'Oh, look, an embryo,' that doesn't make it an embryo. I don't know what they made, but they're not really embryos."Besieged by advocates for and against banning the research entirely, Mr. Bush delayed his decision on the research-funding for five months. Then, on Aug. 9, he announced a compromise. He said experiments on embryonic stem-cell lines that had been created as of Aug. 9 could be funded, but no additional embryos could be sacrificed to obtain cells. Although Mr. Bush's decision won praise from many in the pro-life community for refusing to fund the research it considers immoral, it also sorely disappointed those who wanted an outright ban.The decision also had the effect of focusing attention on the possibility of cloning "quality" embryos to obtain stem cells. If human embryos could be cloned, it would produce a source of cells for research but would also solve a barrier to using stem cells to cure illness.The problem is that patients' bodies tend to reject injected stem cells. Unless researchers find a way to avoid rejection, it is useless to try to develop stem-cell therapies in the first place. Scientists think the most likely approach is to use a cell from the patient and, through cloning, create an embryo containing stem cells that would be genetically identical to the patient's cells. That way the patient would, in effect, be receiving healthy versions of his own cells. The process is called "therapeutic cloning" and is done in five steps:Removing the nucleus from the skin cell of a person with, for example, heart disease or diabetes.Implanting the skin-cell nucleus into a donated human egg from which the nucleus has been removed.Nurturing the altered egg as it transforms the inserted skin-cell nucleus and evolves into a 5-day-old embryo containing stem cells.Removing the embryonic stem cells and "persuading" them to develop into cells that will form heart muscle, for instance, or components of the pancreas.Injecting the manipulated stem cells into the patient, where they will form new heart muscle to replace damaged original tissue or into the islets of the pancreas gland that are responsible for producing the insulin essential for controlling diabetes.Although therapeutic cloning is an appealing scientific solution, it also alarms opponents of stem-cell research, because the embryo produced could instead be implanted into a surrogate mother to produce an adult clone of the patient. They say that if therapeutic cloning is allowed, it will inevitably lead to such reproductive cloning meaning the deliberate use of cloning to produce an infant from cells extracted from the person being copied and without going through the normal egg-fertilization process.So when Advanced Cell Technology claimed on Nov. 25 to have accomplished or nearly accomplished the creation of a cloned human embryo, its actions were instantly and hotly condemned.Mr. Bush and leading congressional conservatives called for quick action to ban human cloning. They accused Advanced Cell of "crossing the line."Mr. Bush told reporters, "The use of embryos to clone is wrong. We should not as a society grow life to destroy it. And that's exactly what's taking place." Religious leaders and politicians around the world joined the president in condemning the company. And many scientists did, too, because they said the company was exaggerating its accomplishments, hoping to position itself in what could some day become a lucrative market for stem cells or for embryo-cloning technology.Mainline scientists insist that no one has successfully cloned a human embryo. They say no reputable scientist would think of trying to clone a human because, even if cloning were morally and socially acceptable, the most reliable cloning techniques are too unreliable by far to justify human-cloning experimentation.Yet there are a few maverick scientists in the world who claim it is currently permissible to try to create a genetic copy of a human and who insist they are working to achieve reproductive cloning. A few weeks ago, for example, the Kentucky-based human cloning advocate and reproduction physiologist Panayiotis Michael Zavos claimed at a medical conference that he was importuned by some 3,000 infertile couples seeking to have "a biological child of their own" through cloning. He said he intended to help them. In reply, Dr. Paul R. Billings, a geneticist and professor at the University of California, said those who attempt to clone humans "should be treated as what they are criminals." He said that attempts to clone animals have shown that cloning is now "unsafe and risky" because, when the offspring don't die, they are mostly born deformed.Biochemist John Morrow, a professor at Texas Tech University in Lubbock, says we are a long way from being able to clone human embryos successfully for any reason. He notes that scientists generally fear that the news reports of 2001 will impel legislators to pass hasty legislation.But as biochemist Larry Goldstein points out, the issue confronting legislators is profound, and the results of their action will necessarily have grave consequences for the health of people around the world."They ought to take their time to thrash this out," Mr. Goldstein said.